How do they know which influenza virus will hit New Zealand?

How do they know which influenza viruses will affect New Zealand?


The World Health Organization (WHO) takes influenza very seriously.  Each year the WHO Information Surveillance Network studies the different strains of influenza and monitors their movements around the globe.  They then decide which strains of the virus are likely to emerge in different parts of the world and provide advice for what strains influenza vaccines should include.